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    <title>Document</title>
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    <script type="text/javascript">
      // 3 7 4 5 1 2
      // 3 7 4 1 6 5 2 
      // 3 4 7 1 5 
      // 3 7 4 1 2 5 
      const first = () =>
        new Promise((resolve, reject) => {
          console.log(3);
          let p = new Promise((resolve, reject) => {
            console.log(7);
            setTimeout(() => {
              console.log(5);
              resolve(6);
            }, 0);
            resolve(1);
          });
          resolve(2);
          p.then((arg) => {
            console.log(arg);

          });
        });

      first().then((arg) => {
        console.log(arg);
      });
      console.log(4);
    </script>
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